dill is being edited for lidavidm 's fork
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1) any way to make dump_session use a file handler instead of a string name?
2) migrate dump_session/load_session to dump_image/load_image?
3) add a string equivalent for dump/load of sessions (i.e. dumps_session)?
4) enable passing of custom __main__
5) StringIO.StringIO and cStringIO.StringIO compatibility
6) ...?
